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Descoberta do conhecimento em base de dados como ferramenta aplicada em processos sucroalcooleiros / A proposal to use KDD as a tool to discovery alcohol and sugar production plant behaviorCunha, Márcio José da 11 February 2011 (has links)
Nos dias atuais, a quantidade de dados armazenados na indústria é considerada extensa e contínua. Nas indústrias de produção de açúcar e álcool, nem sempre todas as variáveis do processo são analisadas devido a imensa quantidade de dados, a diversidade dos setores no processo e pela grande diculdade em saber como se deve analisar tais dados. Este trabalho propõe a utilização do processo da Descoberta do Conhecimento em Base de Dados, o processo KDD, como uma ferramenta para ser aplicada em processos industriais, especicamente no processo de produção de açúcar e álcool. Os experimentos foram realizados com dados obtidos do processo de fermentação, durante a safra sucroalcooleira. Os resultados mostram que é possível aplicar o processo de KDD para este tip o de indústria, podendo ser aplicado como uma ferramenta de previsão de produção de açúcar e álcool. / Nowadays, the amount of data stored in the industry is considered large and continuous. In the sugar and alcohol industrial production, not always all the pro cess variables are analyzed due to the immense amount of data, the diversity of sectors in the process and the great diculty in knowing how to analyze such data. This work proposes the use of proposes the use of the process of Knowledge Discovery in Databases, KDD process, as a tool to be applied in industrial processes, in specically in sugar cane and alcohol pro cess. The experiments are done with Fermentation data process obtained during the sugar and alcohol harvest. The results show that it is possible to apply the KDD pro cess for this type of industry, where it can be used as a forecasting tool for the production of sugar and alcohol.
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Industriella avloppsvatten i Chile : Identifiering av problem samt förslag på åtgärder / Industrial Wastewater in Chile : Identification of Problems and Suggestions for ImprovementRisberg, Anna January 2006 (has links)
Chile and Santiago are struggling with heavy environmental problems as a consequence of urbanisation and industrialisation. In the Santiago region the air is seriously contaminated and most of the rivers are classified as heavily polluted. The aim of this thesis is to survey the industrial fluid waste situation in the Santiago region and to make suggestions on technological improvements or process changes. The purpose is also to study five different enterprises more closely and to give more detailed suggestions for improvement. Another purpose is to summarize relevant Chilean legislation. Information, provided by the supervisory authority, about the release of industrial wastewater to rivers has been analysed. Deep interviews have been made with authorities and consultants. Five enterprises have been visited; a brewery, a dairy, a bakery, a producer of cooked meat and a surface treatment industry. The present treatment of the wastewater was studied at the plants and the information was completed with a questionnaire to the responsible at each company. The contamination load released to the Chilean rivers is heavy. The rivers in southern Chile receive the biggest loads of BOD and SS and the rivers in central Chile were the most exposed to discharges of the metals Cr, Cu, Zn and CN as well as phenols. The industrial discharge into the rivers of Santiago RM and Region VII is also to a large extent characterized by high concentrations of BOD and SS. Large releases of oils and greases, nitrogen and phosphorus are also fairly common, as are too high or too low pH levels. The food industry is the most contaminating sector, but also tanneries have great problems with effluents exceeding limits. All five companies visited share the need to take measures towards more water saving technologies. The brewery, the producer of cooked meat and the surface treatment company also need end-of-pipe-treatment of their wastewater. In many cases, the recommended and most economic alternative is to separate the flows with the highest concentration of polluting substances for internal treatment, while releasing the rest of the wastewater to the outside sewage system. The costs of the suggested changes must be balanced against the present costs for treatment of wastewater and remaining solid waste as well as the costs for alternative treatments. The economic incentives for Chilean companies to invest in wastewater treatment plants or to optimize the processes until today have been few. Cost reductions may be achieved by savings in water consumption and reuse of raw material. Another motive could be to keep “one step ahead” if the discharge limits in the future are tightened up leading to rising costs. / Chile och Santiago brottas med omfattande miljöproblem till följd av urbanisering och industrialisering. I santiagoregionen är luftföroreningarna svåra och de flesta floderna klassas som gravt förorenade av CONAMA, det chilenska naturvårdsverket. Syftet med examensarbetet är att kartlägga situationen i santiagoregionen med avseende på industriell avloppsrening samt att ge förslag på förbättring av teknik eller förändring av processer. Dessutom är syftet att studera fem industrier närmare och att ge mer detaljerade förslag på åtgärder. Syftet är också att ge rekommendationer för fortsatt utveckling av relevant chilensk lagstiftning. Uppgifter från tillsynsmyndigheten för utsläpp till ytvattendrag har studerats och djupintervjuer har gjorts med myndigheter och konsulter. Fem olika industrier besöktes; ett bryggeri, ett mejeri, ett bageri, ett charkuteri samt en ytbehandlingsindustri. Nuvarande hantering av processvattnet studerades på plats och med hjälp av ett frågeformulär kompletterades uppgifterna av ansvariga på företagen. Föroreningsbelastningen på Chiles floder är stor. Floderna i södra delen av landet tar emot störst mängder organiskt material och suspenderat material medan centrala Chiles floder är värst drabbade av utsläpp av metallerna Cr, Cu, Zn och CN samt utsläpp av fenoler. Utsläppen från industrin till floderna i Region Metropolitana och Region VII kännetecknas också i stor utsträckning av höga halter BOD och suspenderat material. Relativt vanligt är också stora utsläpp av oljor och fetter, kväve, fosfor samt för höga eller låga för pH-värden. Det är främst flera olika typer av livsmedelsindustri, som har de största utsläppen till floderna, men även garverierna har stora problem med överskridande av gränsvärden. Gemensamt för de fem besökta företagen är att vattenbesparande åtgärder bör vidtas för att minska volymen avloppsvatten som går till extern eller intern behandling. Bryggeriet, charkuterifabriken och ytbehandlaren behöver även end-of-pipe-rening. Det kan ofta vara lämpligt och mer ekonomiskt att avskilja de flöden som har högst halt av föroreningar till den interna reningsanläggningen. Resten av avloppet kan i vissa fall släppas ut på avloppsnätet. Kostnader för föreslagna åtgärder måste vägas mot aktuella kostnader för behandling av avlopp och restprodukter, samt kostnader för alternativa behandlingar. Incitamenten, bl a de ekonomiska, för chilenska företag att skaffa eget reningsverk eller att resurseffektivisera produktionen har hittills varit små. Kostnadsminskningar kan uppnås genom sänkt vattenförbrukning samt återanvändning av råmaterial. Ytterligare en drivkraft kan vara att ”ligga steget före” om utsläppskraven i framtiden skärps och kostnaderna därmed ökar.
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Beitrag zur Qualitätssicherung in Gießereien durch die Anwendung statistischer MethodenStrehle, Matthias 20 December 2012 (has links) (PDF)
Es werden die Voraussetzungen für die Anwendung statistischer Methoden in Seriengießereien dargestellt. Dazu wurde zunächst anhand einer umfangreichen Literaturrecherche aufgezeigt, dass der Stand der Technik deutliche Defizite aufweist. Für die Verwendung statistischer Methoden, mit dem Ziel der Ausschussreduktion oder Prozessoptimierung, ist eine Datenbank anzulegen, in der jedem Gussteil eindeutig alle qualitätsrelevanten Prozessparameter zugeordnet sind. In Gießereien werden eine Vielzahl von Prozessdaten gemessen und auf unterschiedlichen Computern gespeichert, jedoch ohne Zusammenhang zum Gussteil und dessen Qualität. Eine Zusammenführung der ungenutzten Daten im Nachhinein ist nicht möglich. Die Stoffströme (Sande, Kerne etc.) wurden vom Rohmaterial bis hin zur Gussteilqualität verfolgt (z. B. mit RFID, Infrarotpyrometer). Es wurde ein Ablaufplan über die Vorgehensweise erstellt und in mehreren Gießereien angewandt. Das Ergebnis war eine vollständige Datenbank der Prozessparameter und Gussteilqualitäten, an der mittels statistischer Methoden die Ursachen für Gussfehler identifiziert worden sind.
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The integration of Dow's Fire and Explosion Index into process design and optimization to achieve an inherently safer designSuardin, Jaffee Arizon 30 October 2006 (has links)
The integration of the safety parameter into process design and optimization is
essential. However, there is no previous work in integrating the fire and explosion index
(F&EI) into design and optimization. This research proposed a procedure for integrating
safety into the design and optimization framework by using the safety parameter as
optimization constraint. The method used in this research is DowâÂÂs Fire and Explosion
Index which is usually calculated manually.
This research automates the calculation of F&EI. The ability to calculate the
F&EI, to determine loss control credit factors and business interruption, and to perform
process unit risk analysis are unique features of this F&EI program. In addition to F&EI
calculation, the F&EI program provides descriptions of each item of the penalties,
chemicals/materials databases, the flexibility to submit known chemical/material data to
databases, and material factor calculations. Moreover, the sensitivity analyses are
automated by generating charts and expressions of F&EI as a function of material
inventory and pressure. The expression will be the focal point in the process of
integrating F&EI into process design and optimization framework. The proposed procedure of integrating F&EI into process design and
optimization framework is verified by applying it into reactor-distillation column
system. The final result is the optimum economic and inherently safer design for the
reactor and distillation column system.
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Monitoring of an Antigen Manufacturing Process Using FluorescenceZavatti, Vanessa 12 June 2015 (has links)
Bordetella pertussis is one of two Gram-negative bacteria responsible for causing whooping cough in humans, a highly contagious disease that infects the human upper respiratory tract. Whole-cell and acellular vaccines have been developed but due to side-effects resulting from whole-cell vaccines, acellular vaccines are currently preferred to prevent this disease. A second bacterium known to cause whooping cough is Bordetella parapertussis, but since it causes less aggressive symptoms, only B. pertussis is utilized in the manufacture of the vaccine. One acellular vaccine is based on four virulence factors: pertussis toxin (PT), filamentous hemagglutinin (FHA), pertactin (PRN), and fimbriae (FIM).
The focus of this thesis was to explore the use of spectrofluorometry for monitoring and forecasting the performance of the upstream and downstream operations in the PRN purification process at Sanofi Pasteur. The upstream fermentation process includes a series of reactors of increasing volume where the microorganism is grown under controlled conditions. The PRN purification process involves a series of sequential steps for separating this protein from other proteins for later use in the vaccine. The PRN is precipitated in three steps with ammonium sulphate at three different concentrations. The pellet is collected by centrifugation and dissolved in a buffer solution followed by chromatographic separation. The run-through is then ultra-filtered and diafiltered in two separate steps. The resulting concentrate is dissolved in water and subjected to another chromatographic step and diafiltration. The final filtration of PRN involves a pre-filtration and sterile filtration. Finally, the samples are collected for quality control.
The objective of this work was to monitor the process at different steps of the upstream and downstream purification process by multi-wavelength fluorescence spectroscopy in combination with multi-variate statistical methods. From the spectra, it was possible to identify fluorescent compounds, such as amino acids and enzyme cofactors, without performing an additional pre-treatment or purification step. Also, the identification of conformational changes in proteins and formation of complexes, such as NAD(P)-enzyme complex, was possible based on the shift in the emission peaks of the compounds identified. These results demonstrated the feasibility of using this tool for qualitative evaluation of the process.
Multivariate methods, such as PCA and PLS, were used to extract relevant information and compress the fluorescence data acquired. PCA was effective for correlating variability in the yield of pertactin to a particular fluorescence fingerprint. As a result of the study, it was concluded that a possible source of variability in the productivity that is observed might be a metabolic shift during the fermentation steps that leads to the accumulation of NAD(P)H (or NAD(P)H-enzyme complex) probably due to oxygen transfer limitations. This conclusion was reached after investigating changes in the dissolved oxygen, aeration, agitation, supplementation time and key metabolites (lactate, glucose, glutamine) profiles. The correlation of these parameters with low productivity it was not straightforward; however, some consistencies were observed, for example, high levels of glutamine in batches with low productivity. This fact might be related to the start of the supplementation time, which may be related to the dissolved oxygen, since the addition of the supplement is done manually when an increase of the dissolved oxygen is detected. It is believed that this factor is related to the low production of protein product, such as pertactin.
By means of PLS, it was possible to build regression models that allow for predicting the final concentration of pertactin from the fluorescence measurements. The models were built using the new variables obtained from data compression performed with PCA, and the final pertactin concentration measured by a Kjeldahl test. With this method, two regressions were constructed: (i) between NAD(P)H-enzyme complex spectra from the fermenters and pertactin concentration and (ii) between the pertactin fluorescence spectra from the last step of purification and pertactin concentration. A third model was built using the protein content, the NAD(P)H-enzyme complex content in the fermenters and pertactin concentration.
Attempts were made to identify the possible enzyme that may bind to NAD(P)H, assumed to be a dehydrogenase. Substrates for different enzymes were employed with the objective of measuring changes in the fluorescence of the characteristic peak for this binding (Ex/Em=280/460 nm). Major changes were detected after addition of the substrates oxaloacetate, ubiquinone and succinate dehydrogenase. Since changes were detected with more than one substrate, it was not possible to unequivocally identify the enzyme; however, the results provide some insight into what may be happening at the metabolic level.
The work carried out in this thesis involved both analysis of samples provided or collected by the industrial sponsor as well as analysis of samples prepared at the University of Waterloo for measurement, interpretation and calibration. The proposed fluorescence-based method was found suitable for assessing protein quantity as well as for providing an indication of possible protein aggregation and conformational changes. Future work will be required to identify the exact source of variability in the production of pertactin, by means of monitoring the evolution of fermentation, NAD(P)H and ATP measurements, and oxidation redox potential assays.
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Coagulation Optimization to Minimize and Predict the Formation of Disinfection By-productsWassink, Justin 04 January 2012 (has links)
The formation of disinfection by-products (DBPs) in drinking water has become an issue
of greater concern in recent years. Bench-scale jar tests were conducted on a surface water to evaluate the impact of enhanced coagulation on the removal of organic DBP precursors and the formation of trihalomethanes (THMs) and haloacetic acids (HAAs). The results of this testing
indicate that enhanced coagulation practices can improve treated water quality without
increasing coagulant dosage. The data generated were also used to develop artificial neural networks (ANNs) to predict THM and HAA formation. Testing of these models showed high correlations between the actual and predicted data. In addition, an experimental plan was developed to use ANNs for treatment optimization at the Peterborough pilot plant.
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Coagulation Optimization to Minimize and Predict the Formation of Disinfection By-productsWassink, Justin 04 January 2012 (has links)
The formation of disinfection by-products (DBPs) in drinking water has become an issue
of greater concern in recent years. Bench-scale jar tests were conducted on a surface water to evaluate the impact of enhanced coagulation on the removal of organic DBP precursors and the formation of trihalomethanes (THMs) and haloacetic acids (HAAs). The results of this testing
indicate that enhanced coagulation practices can improve treated water quality without
increasing coagulant dosage. The data generated were also used to develop artificial neural networks (ANNs) to predict THM and HAA formation. Testing of these models showed high correlations between the actual and predicted data. In addition, an experimental plan was developed to use ANNs for treatment optimization at the Peterborough pilot plant.
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Optimal Scheduling for Biocide and Heat Exchangers Maintenance Towards Environmentally Friendly Seawater Cooling SystemsBinmahfouz, Abdullah 2011 August 1900 (has links)
Using seawater in cooling systems is a common practice in many parts of the world where there is a shortage of freshwater. However, biofouling is one of the major operational problems associated with the usage of seawater in cooling systems. Microfouling is caused by the activities of microorganisms, such as bacteria and algae, producing a very thin layer that sticks to the inside surface of the tubes in heat exchangers. This thin layer has a tremendously negative impact on heat transferred across the heat exchanger tubes in the system. In some instances, even a 250 micrometer thickness of fouling film can reduce the heat exchanger's heat transfer coefficient by 50 percent. On the other hand, macrofouling is the blockage caused by relatively large marine organisms, such as oysters, mussels, clams, and barnacles. A biocide is typically added to eliminate, or at least reduce, biofouling. Typically, microfouling can be controlled by intermittent dosages, and macrofouling can be controlled by continuous dosages of
biocide.
The aim of this research work is to develop a systematic approach to the optimal operating and design alternatives for integrated seawater cooling systems in industrial facilities. A process integration framework is used to provide a holistic approach to optimizing the design and operation of the seawater cooling system, along with the
dosage and discharge systems. Optimization formulations are employed to systematize the decision-making and to reconcile the various economic, technical, and environmental aspects of the problem. Building blocks of the approach include the biocide water chemistry and kinetics, process cooling requirements, dosage scenarios and dynamic profiles, biofilm growth, seawater discharge, and environmental regulations.
Seawater chemistry is studied with emphasis on the usage of biocide for seawater cooling. A multi-period optimization formulation is developed and solved to determine:
* The optimal levels of dosing and dechlorination chemicals
* The timing of maintenance to clean the heat-exchange
* The dynamic dependence of the biofilm growth on the applied doses, the seawater-biocide chemistry, the process conditions, and seawater characteristics for each time period.
The technical, economic, and environmental considerations of the system are accounted for and discussed through case studies.
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A importância do ponto de operação nas técnicas de self-optimizing controlSchultz, Eduardo dos Santos January 2015 (has links)
A otimização de processos vem se tornando uma ferramenta fundamental para o aumento da lucratividade das plantas químicas. Diversos métodos de otimização foram propostos ao longo dos anos, sendo que a otimização em tempo real (RTO) é a solução mais consolidada industrialmente, enquanto que o self-optimizing control (SOC) surge como uma alternativa simplificada, com um menor custo de implantação em relação a esse. Neste trabalho são estudados diversos aspectos da metodologia de SOC, iniciando pela análise do impacto do ponto de operação para o desenvolvimento de estruturas de controle auto-otimizáveis. São propostas modificações na formulação do problema de otimização de SOC de modo que as variáveis controladas sejam determinadas no mesmo problema de otimização em que é escolhido o ponto de operação, permitindo a redução da perda do processo. De forma a analisar a influência da dinâmica nos resultados obtidos, é realizado um estudo comparativo da perda gerada no processo ao longo da operação para as estruturas de otimização baseadas em RTO e em SOC. Com base nos resultados obtidos para uma unidade didática, mostra-se que o comportamento dinâmico do distúrbio possui grande influência na escolha da técnica de otimização, quebrando a ideia de que o RTO é um limite superior do SOC. A aplicação industrial das técnicas clássicas de SOC é validada em uma unidade de separação de propeno, baseada em uma unidade real em operação. A partir da modelagem do processo em simulador comercial, foram geradas as variáveis controladas que permitam uma perda aceitável para a unidade, comprovando a viabilidade de implantação da metodologia em unidades reais. / Process optimization has become a fundamental tool for increasing chemical plants profit. Several optimization methods have been proposed over the years, and real-time optimization (RTO) is the most consolidated solution industrially while self-optimizing control (SOC) appears as a simplified alternative with a lower implementation cost. In this work several aspects of SOC methodology are studied, starting from the analysis of the impact of operating point in the development of self-optimizing control structures. Improvements are proposed in SOC optimization problem formulation where controlled variables are determined in the same optimization problem that operating point, thus reducing significantly process loss. In order to analyze the influence of dynamics on the results, a comparative study is accomplished comparing the loss generated in the process throughout the operation for optimization structures based on RTO and SOC. With the results generated for a toy unit, it is shown that the disturbance dynamic behavior has a great influence on choosing the optimization technique, breaking the idea that RTO is an upper limit of SOC. The industrial application of classical SOC techniques is tested on a propylene separation unit, really operating nowadays. The process was modelled in a commercial simulator and with this model it was generated the best set of controlled variables, based on SOC, that achieve an acceptable loss for the unit, showing that the methodology can be applied in in real units.
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Modelling and control of crystal purity, size and shape distributions in crystallization processesBorsos, Akos January 2017 (has links)
Crystallization is a key unit operation used for obtaining purified products by many process industries. The key properties of the crystalline products, such as size and shape distribution, purity and polymorphic form are controlled by the crystallization process. All these properties impact significantly the downstream operations such as drying or filtration. Therefore, monitoring and controlling this process is fundamental to ensure the quality of the final product. Process analytical technology (PAT) brings numerous new methods and opportunities in the process analytics and real time process monitoring systems, which can be integrated into the control algorithm and provide high level optimal control strategies as well as deeper understanding of the process. Process monitoring helps develop mathematical models which can, in one hand, help in better understanding the processes and consecvently the development and application of advanced control methods in order to achieve better product quality. In this work, image processing and image analysis based direct nucleation control (IA-DNC) is developed in order to investigate the evolution of the crystal properties, such as crystal size, and crystal shape distribution. The IA-DNC approach is also compared to alternative DNC techniques, in which particle number were measured by Focused Beam Reflectance Measurement (FBRM) in order to control crystal size. A control approach is introduced that control the nucleation and disappearance of crystals during cooling and heating segments related to the changes of the number of counts (measured by Particle Vision Measurment, so called PVM or combination of FBRM and PVM). The approach was applied to investigate crystallization of compounds with different behavior: potassium dihydrogen phosphate (KDP) water, contaminated KDP -water and Ascorbic acid water systems. The results demonstrate the application of imaging technique for model-free feedback control for tailoring crystal product properties. The second main aim of the thesis is to investigate and control crystallization processes in impure media in the presence of multiple impurities, with an impact on the crystal shape via growth kinetics. The broad impact of the crystal growth modifiers (impurities) on the growth kinetics is observed in real time by using in situ video imaging probe and real-time image analysis. A morphological population balance model is developed, which incorporates a multi-site, competitive adsorption mechanism of the impurities on the crystal faces. The kinetic parameters of primary nucleation, growth and impurity adsorption for a model system of potassium dihydrogen phosphate crystallization in water in the presence of two impurities, were estimated and validated with experimental results. It was demonstrated that the model can be used to describe the dynamic evolution of crystal properties, such as size and aspect ratio during crystallization for different impurity profiles in the system. Manual, feedback and hybrid feedback-feedforward control techniques are developed and investigated numerically for continuous processes, while model-based and model-free control approach for crystal shape are developed for batch processes. The developed morphological population balance model is implemented and applied in the model-based control approaches, which are suitable to describe multicomponent adsorption processes and their influence on the crystal shape. Case studies show the effectiveness of crystal growth modifiers based shape control techniques. Comparison of different control approaches shows the effectiveness of the techniques. The third part of the thesis deals with purification of crystals when adsorption of impurities on crystal surfaces and its incorporation into crystals are considered. A purification method, called competitive purity control (CPC) is proposed and investigated. A morphological population balance model, including nucleation, growth and competitive impurity adsorption kinetics is developed to describe the case when multiple impurities can adsorb competitively on the crystal surface. The model is also combined with liquid phase chemical reaction model, in order to investigate the purity control case when an additive is introduced in the system that reacts with the impurity forming a non-adsorbing reaction product. Both competitive purity control approaches proposed: the adsorption based competitive purity control (A-CPC) and the reaction based competitive purity control (R-CPC); are investigated using detailed numerical simulations then compared with the alternative widely used purification method, called recrystallization. In the last contribution chapter, an integrated process optimization of a continuous chemical reactor and crystallizer is performed and studied numerically. The purpose of this study is to show the way in which the byproduct produced in the chemical reactor may affect the crystallization process and how its negative effect can be reduced by applying integrated process optimization. Sensitivity analysis of the system was performed by considering the flow rate and the concentration of substances in the input stream of the chemical reactor as manipulated process variables. Model based integrated process optimization and the sensitivity analysis in order to obtain improved quality product in terms of crystal size, shape and purity.
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